Bhāskarācārya, Bapu Deva Sastri. Ancient system of Hindu astronomy (English में). Harvard University. Baptist mission press, 1861.सीएस1 रखरखाव: नामालूम भाषा (link)
Bhāskarācārya, Bapu Deva Sastri. Ancient system of Hindu astronomy (English में). Harvard University. Baptist mission press, 1861.सीएस1 रखरखाव: नामालूम भाषा (link)
Vitruvius, Marcus Pollio (1914). "VII". प्रकाशित Howard, Alfred A. (संपा॰). De Architectura libri decem [Ten Books on Architecture] (अंग्रेज़ी में). Herbert Langford Warren, Nelson Robinson (illus), Morris Hicky Morgan. Harvard University, Cambridge, Massachusetts: Harvard University Press. पृ॰ 215.
Machamer, Peter; Miller, David Marshall (2021), Zalta, Edward N. (संपा॰), "Galileo Galilei", The Stanford Encyclopedia of Philosophy (Summer 2021 संस्करण), Metaphysics Research Lab, Stanford University, अभिगमन तिथि 2023-04-08
Smith, George (2008), Zalta, Edward N. (संपा॰), "Newton's Philosophiae Naturalis Principia Mathematica", The Stanford Encyclopedia of Philosophy (Winter 2008 संस्करण), Metaphysics Research Lab, Stanford University, अभिगमन तिथि 2023-04-08